Abstract

Dichotic masking studies using noise are commonly referenced in regard to their implications for “cocktail party listening” wherein target and maskers are speech. In the present study masker decision weights (MDWs) are reported suggesting that speech and noise are processed differently in dichotic masking. The stimuli were words or Gaussian-noise bursts played in sequence as masker-target-masker triads. The apparent location of words (noise bursts) from left to right was varied independently and at random on each presentation using KEMAR HTRFs. In the two-interval, forced-choice procedure listeners were instructed to identify whether the second-interval target was to the left or right of the first. For wide spatial separations between target and masker noise-MDWs were typically negative, indicating that target location was judged relative to the masker. For small spatial separations between target and masker noise-MDWs were typically positive, suggesting that target location was more often confused with the masker. For both spatial separations, however, word-MDWs were close to zero, implying that the masker served to distract attention from the target without itself being given significant weight. The results are consistent with an interpretation in which spectral dissimilarities among words generally serve to reduce confusions and relative comparisons among words.